Yieldable bearing for centrifugal machines



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/IYVENTOR effe/ Patented Mar. 29, 1921.

w W e m 2 p my n UNITED STATES PATENT OFFICE.

MEREDITH LEITCH, POUGHKEEPSlE, NEW' YORK, ASSIGNOR TO THE DE LAVAL SEPARATOR COMPANY, Oli' NEW' YORK, N. Y., A CORPORATON NEW JERSEY.

Levens/i.

Specification of Letters Patent.

Patented Mar. 29, 1921.

Application filed January 8, 1919. Serial No. 270,137.

To elli whom t may concern:

linoivn that l, MnRnnrTI-t LnI'rGi-r, a citizen ot' the United States, residing at Poughkeepsie, county ot Butchess, and bibite ot New York, have invented a new and uset'ul improvement in Yieldable Bearings :tor Centrifugal Machines, ot which the i'olloiving is a. tull, clear, and exact description, reterence being had to the accompanying drawings, which torrn a part oi:l this specitication.

.ll/.ly invention relates to spring bearings particularly adapted Jfor centrifugal machinery.

ln such apparatus centrifugal liquid sepa {ators and clariiiers, Which necessarily revolve at high speed and in which it is impossible to always have the center et' gravity exactly coincide with the geometrical e inter, the revolving spindle is provided with a bearing held in the center ot the frame by a spring. This spring permits slight Inovement ot the bear' .1g so that the spindle and boivl 'may revolve about the center ot gravity.

To give the have a slight resistance 'to small movements but a rapidly increasing resistance as the amplitude et the movement increases. With the ordinary springs employed tor this purpose the resistance to movement lis proportional to the movement.

The object of my invention is to provide a spring bearing in which the rate ot increase ot resistance to movement shall increase with the movement.

The invention comprises a bearing, a restraining spring inclosing `the lecturing,v and a support inclosing the spring, the support and bearing being so termed and the spring being so anchored and shaped that as the bearing is more and more displaced from its central position the tree length ot the spring, at the side toward Which the bearing moves, vvill be more and more reducedand thereby otter a more than proportional resistance to further movement.

To illustrate my invention I herein disclose tivo embodiments ot my invention. In the lirst embodiment the spring is supported at the ends and is loaded at the center, the support being of such :form that as the spring yields the points of contact with` the support approach the center of the support best results the spring should and the abutment ot the load being ot' such term that as the spring yields the points ot contact with the spring will approach the ends, whereby the effective length of spring will be reduced and its resistance increase more rapidly than the movement.

ln the second embodiment ot the invention tlat springs are each supported at one end and provided with an abutment which, when the bearing is in the center ot the trame, bears on only the free end otl the spring, but which, when the bearing is moved on one side ot the center, bears on the spring nearer the anchorage thus, as in the iirst embodiment, reducing the etlective length ot the spring, While its resistance increases more rapidly than the movement.

My invention, however, is not restricted to the specific embodiments thereof herein particularly disclosed.

ln the aceom'ianying drawings-m Figure l is vertical sectional view ot a spindle, bearing, support and spring embodying one torni oft my invention, the spindle being shown in a central position, and the spring being shown only in one plane.

Fig. 2 is a view, similar `to Fig. l, with the spindle at one side of the center.

Fig. 2:3 is a developed view of the spring oi" Figs. l and 2.

Fig. 4t is a view, similar to Fig. l, of a modification.

Fig. 5 is a view, similar to Fig. 2, of the modification of Fig. 4.

Fig. 6 is a developed view ot the spring ot Figs. l and Reterring tiret to the embodiment ot my invention illustrated in Figs. Il, 2 and 3:

'lhespindle a oi a centrifugal bowl (not shown) is guided on a bearing t, laterally rest 4ained by a spring c supported by an abutment composed ot tivo parts d and e. The spring-is composed of a plurality ol' flat spring fingers joined togetherat the center, as shown in Fig. 3, and bent so that When tree they collectively torni a cylinder. The outside et the bearing is preferably spherical in term. The inside diameter of the abutment or support is smallest at the top and bottom and greatest midway between its top and bottom, the inside surface ot the support tapering toward the axis ot rotation ot the spindle from its mid-circumference toward both its top and bottom.

The spring c is et such length as to surround the bearing` when applied thereto. The smaller diameters ot the support are less than the outside diameter of the spring when wrapped tightly around the bearing and the spring contacts with the support only along the upper and lower edges oit the spring, as at g and 7L. By reason orP the shape ot' the bearing, the spring touches the bearing only along the narrow zone including the midcircumterence of both, as at j?. rEhis leaves a maximum length ot lree spring and allows the bearing to be easily moved tor a short distance. When the bearing is moved to one side of the center, as shown in Fig. 2, the spring, on the side toward which it moves, is bent around and contacts with the bearing for a greater or less distance on opposite sides of the mid-circumference et both, while at the same time the end portions of the spring, tor a greater or less distance, are bent against and Contact with the support. rllhus, in Fig. 2, it the spindle moves away from the center as tar as indicated, the spring contacts with the bearing from a to y' and with the support between one end ot the spring and 7c and between the other end ot the spring and Z, leaving, as shown, very short lengths oi tree spring i L and j Z, which will be stii and oller great resistance to movement. At the same time, the spring, on its opposite side, becomes straighter and causes very little pressure to assist the increment.

To enable the spring to operate as described, the middle diameter ot' the support ci e should be greater than the maximum diameter o'l the bearing plus twice the thickness o the spring, and the end diameters ot the support should be less than the maximum diameter of the bearing plus twice the thickness of the spring.

In the form shown in Figs. et, 5 and 6, fm represents the spindle, a the bearing and o the support 'for the spring p, which is of the type set forth in Patent No. 1 l,'l.0,90, issued August 18, 1914i, to T. H. Miller, but differing from the specific construction et the patent in that the lingers are bent inward instead of outward and are curved on the arc of a circle instead ot irregularly. The spring tingers in'this case are attached to a cylinder which lits a cylindrical bore in a machine trame, making them particularly adaptable for .use to replace Miller springs in existing machines, or" which there are .many thousands in use.

With the bearing in the central position, as shown in Fig. 4, the springs y) touch the bearing n. at only the points r and s, leaving a great length of free spring and permitting easy movement of the bearing. TWhen the bearing is forced to one side ol the center, the lingers on that side bend and their points of contact with the bearing approach its center, as at t and u, leaving relatively short free springs, which will be still. and olier great resistance to further movement, while the lingers on the opposite side will have only their extreme ends in light contact with the. bearing, giving negligible pressure to assist movement.

rlhe restraining force of an ordinary spring may be described by the equation liza/'y in which F is the restraining Vtorce, n; is a constant and z/ is the displacement 'from a central position. The restraining torce ol one et my springs would be represented more nearly by the equation Fze'y with the exponent n. greater than l.

in Letters Patent No. lfO-l, issued September T, 1920 on an application lilcd ol even date herewith, l have shown and described the yieldablc bearing illustrated in Figs. Ll, 5 and 6. The claims in said patent, are applicable to such bearing, but not lo the bearing shown and described in Figs. l. and 3. Herein the novel features common to both bearings are claimed, and certain features embodied in the bearing ol" Figs. i.. 2 and 3, but not embodied in thc bearing` el' Figs. Li, 5 and 6, are also claimed.

llaving now full described my invention, what claim and desire to protect hy Letters Patent isl. A yieldable bearing for a centrifugal machine comprising a bearing haring a sphere-like convex surlace, a surrounding support, and a spring confined between the bearing and support and extendinj.;- along the axis ot the bearing und having a lree end displaceable in the direction ol' said axis in the, lateral movement of the bearing.

2. 5 vicldable bearing lor a centrilu il gal machine comprising a bearing having :1 sphere-like convex surface, a surrounding` support, and spring fingers extending along the axis of the bearing between said members and having tree ends slidable in the direction of said axis along one ol said nicmbers to reduce the eli'ective length ol the spring lingers at the side toward which the bearing moves.

3. A yieldable bearing for a centrifugal machine comprising a bearing havinfr a sphere-like convex surface, a surrounding support, and spring fingers extending along the axis of the bearing between said members, said lingers having free ends and bendable, when the bearing moves toward the support, to increase the contacting part of the length of a linger at the side toward which the bearing moves and thereby reduce the eliective lengths of such linger.

e. A yieldable bearing for a centrifugal machine comprising a bearing having a sphere-like convex surface, a surrounding support, and spring lingers confined between the axis and support and extending along the axis of its bearing and having free ends which, in the lateral movement of the bearllo liu)

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ing, are displaceable, in the direction of the axis, in one direction at the side toward which the bearing moves and in the opposite direction at the side away from Which the bearing moves.

5. A. yieldable bearing for a centrifugal machine comprising a bearing having a sphere-like convex surface, a surrounding support, and spring fingers confined between the axis and support and extending along the axis of its bearing and having free ends which, in the lateral movement of the bearing, are bendable to increase the contacting lpart of the length of a linger at the side toward which the bearing moves and decrease the contacting part of the length of a finger at the opposite side and thereby rcduce the effective length of the spring at one side and increase its effective length at the opposite side.

t3. In a yieldable support for a rotatable spindle, the combination of the spindle, a bearing guiding the spindle, a support surrounding the bearing and spindle, and a spring confined between the bearing and support, said spring comprising spring sections extending along the axis of the spindle between relatively distant points on the bearing and support respectively When the,

bearing is in a central position, the bearing having a spherical-like surface so that, as it moves laterally, it shortens the effective free length of a spring section at the side toward which the bearing moves.

T. In a yieldable support for a rotatable spindle, the combination of the spindle, a bearing, having a sphere-like surface, guiding the spindle, a support surrounding the bearing Whose inner Wall, from its midcir cumference, slopes in opposite directions toward the axis of rotation, and a spring, confined between the bearing and support, 'Whose upper and lower portions engage the support and whose central portion engages the sphere-like surface of the bearing.

8. A yieldable bearing comrpising a supporting member having its middle portion largerl in diameter than the ends, a bearing having a spherical-like exterior surface, and an intermediate spring, the middle diameter of the support being greater than the maximum diameter of the bearing memberplus twice the thickness of the spring and the end diameters of the support being less than the maximum diameter of the bearing plus twice the thickness of the spring.

9. A yieldable bearing for a centrifugal machine, comprising a bearing having a sphere-like convex surface, a surrounding support consisting of two frusto-conical chambers With their bases together and a spring having fingers normally parallel to form a cylinder, the relative shape and of the sphere and chambers being such that, with the bearing in the center, the centers of the spring ngers conform to the curve of the sphere and the ends form curves to which the conical Walls are tangent.

i0. A yieldable bearing for a centrifugal machine comprising a bearing having a sphere-like convex surface, a surrounding support consisting of two :truste-conical chambers with their bases together and a spring having fingers normally parallel to form a cylinder, the relative shape and sizes of the sphere and chambers being such that, with the bearing in the center, the centers of the spring fingers conform to the curve of the sphere and the ends form curves to which the conical Walls are tangent, While displacement of the bearing from the center causes on the side toward which it moves an increase of conformity of the springto the sphere and an increase of the tangency of the spring to the conical Walls.

ln testimony of which invention, I have hereunto set my hand, at Poughkeepsie, N. Y., on this 31st day of December, 1918i MEREDITH LEITCH 

